The invention relates to a pipe union between two pipe ends to be joined in end-to-end relation to one another, onto each of which a flange, at least one clamping element, and one chamber element are fitted, which can be braced against one another and which among them enclose a shaped seal.
A pipe union is disclosed, for example in German patent disclosure document German Offenlegungsschrift No. 32 06 570. Here, the flange has a circular clamping chamber which is open toward the butt joint. Clamping elements are inserted into this clamping chamber, which elements comprise a convex disk that is supported with its radially outwardly located clamping rim on an annular clamping face of the clamping chamber. In the relieved state, the clamping element protrudes outward beyond the end face of the associated flange. The chamber element has an approximately triangular outer contour and is provided with a sealing chamber that is open toward the butt joint and is conical in shape, that is, it tapers toward the adjacent flange. The outer contour of the shaped seal is approximately equivalent to that of the two sealing chambers in the two chamber elements, but is overdimensioned so that if the two chamber elements are pressed against one another, a pressure that is directed axially and radially inward is exerted upon the seal. In order to be able to brace the two flanges against one another, three screw bolts are provided, distributed uniformly about the circumference of the flange, while hexagonal socket screws are provided for bracing the two chamber elements. To assemble the pipe union, first the two chamber elements are screwed together using the hexagonal socket screws, once the seal has been fitted accurately over the butt joint, then the clamping elements are pushed to a stop against the chamber elements, and next the flanges are pushed to a stop against the clamping elements. The flanges are braced against one another by tightening the screw bolts. The result is the above-explained deformation of the clamping elements, which by this means effect a frictional union, and if there is a scarfed inwardly located clamping rim a form-fitting union as well, between the flange and the pipe end.
The above-described structure is complicated in design and difficult to assemble.